Refrigerating apparatus



Jan. 30, 1945. w. GIFFARD REFRIGERATING APPARATUS Filed Sept. 1:5, 1943 I iuvmdm wmmg Giffard grams Patented Jan. 30, 1945- REFBIGERATING'APPARATUS Whitney Gifiard, Detroit, Mich, assignor to- Nash-Kelvinator Corporation, Detroit, Mich.,

a corporation of Maryland Application September 13, 1943, Serial No. 502,137

4 Claims. (01. 62-89) ratus of the multiple temperature type.

One of the objects of my invention is to provide a new and improved arrangement for maintaining different temperatures and difierent relative humidities in a plurality of zones.

Another object of my invention is to provide a refrigerator cabinet with its interior divided into a sub-freezing compartment, a low temperature high humidity compartment and a low tem. perature low humidity compartment with the circulation of air being limited between the sub freezing compartment and the low and high humidity compartments'and direct circulationbetween the low and high humidity compartments being entirely prevented, and to cool the low temperature compartment by the absorption of heat through the exterior walls and slightly by' the partitioning member between the high and low humidity compartments which partitioning member is cooled by the air circulating between the low humidity and sub freezing compartments.

Further objects and advantages of the present invention will be apparent from the'following description, reference being had to the accompanying drawing, wherein a preferred form of the present invention is clearly shown.

In the drawing:

Fig. 1 isa front view in elevation of a preferred embodiment of my invention partly in cross-section and partly broken away;

Fig. ,2 is a side view in elevation of the embodiment shown in Fig. 1 partly in elevation and partly broken away;

Fig. 3 is a front view in elevation of the embodiment shown in Fig, 1 with parts 'broken away; and

Fig. 4 is a perspective view of a portion of the embodiment shown in Fig. 1.

In accordance with my invention, I have provided a new and improved arrangement for maintaining a plurality of zones in a food storage chamber of a refrigerator cabinet at diiierent temperatures and different humidities. Across the top of the food storage chamber I have disposed a primary refrigerant evaporating element having a rapid freezing zone and a low temperature storage zone within its confines and having air cooling surfaces outside of said zones. Below the evaporating element the food storage chamber is divided into two compartments by means of a vertical partition. One of these compartthe primary evaporating element, there being some circulation of air between the compartment and the evaporating element through the top of the compartment. A dry food storage zone is thus provided in this compartment, any moisture condensing out the air being frozen on the primary evaporating element. The other compartment is maintained at a high humidity by limiting the circulation of air between it and the primary evaporating element. This restriction on circulation is accomplished by'horizontal imperforate members arranged in vertically spaced relationship with the compartment and across the top thereof, some of the members servingas article supporting shelves. These members are arranged in spaced relationship to the walls of the compartment to permit only limited circulation of air. A secondary evaporating element is employed to lower the temperature of this compartment to the desired degree. .A door closes the front of this compartment to keep the humidity conditions within certain limits within this compartment. Thus a high temperature and high humidity zone is provided in this second compartment. By the above arrangement, several zones of definite temperatures and humidities are provided. One zone is maintained at its desired temperature and humidity substantially independently of other zones. Since the zones in this arrangement lie side by side rather than on top of one another, the cold air which naturally descends to the bottom of the zone has little influence on the temperature of the adjoining zone. It is thus possible by this arrangement to provide zones having sharply defined temperature and humidity diiferences instead of zones which have temperature and humidity con-.

ditions which approach each other as the separating boundaries are approached. I

Referring to the drawing, numeral 20 designates, in general, a refrigerator cabinet having a food storage chamber 22 and a machine compart'ment 24. The cabinet is provided with in-' sulated walls which include side walls 26 and 28, top wall 30, bottom wall 32 and rear wall 34. These insulated walls are formed by an outer lining member 36, an inner lining member 38 with insulation ll interposedr therebetween. The inner lining member 38 forms the walls-of the food storage chamber 22. Access to the food storage chamber is aflorded through an opening which is closed by a door 44. Door 46 is also provided afiording' access to the machine compartment 24.

ments is cooled by cold convection currents from Within the food storage-chamber 22 there is element 62 and a low temperature storage zone 64. Shelves 6B are supported horizontally between the partition 60 and the refrigerated side wall 52 to provide a support for receptacle 68. If desired, additional refrigerant evaporating means may be associated with one or more of these shelves 66 to enhance a rapid freezing effect produced by the evaporating element 50. Below the evaporating element 50 is disposed a partition wall I (which divides the lower portion of the food storage chamber 22 into two compartments I2 and I4 which are open at the top thereof. Over the top of these two compartments there is disposed a sheet metal drip pan 00 which is supported from the side walls of the inner linin member 38 by means of brackets 82. I'his'drip pan slopes downwardly to a point over the compartment I2 where a slot 84 is provided to permit drainage of the moisture collected in the drip pan. A large receptacle 86 is suspended in compartment 12 below the drip pan by means of brackets 80. The drip pan is slightly spaced about its outer edges from the walls of the inner lining member to permit a limited circulation of air between the interior of the compartment I4 and the compartment in which the refrigerant evaporating element 50 is disposed. A glass shelf 80 is supported within compartment I2 near the bottom thereof by brackets 92. The temperature below this shelf is higher than the temperature thereabove. If desired, an openwork'shelf may be used. If so; the temperature therebelow will be the same as thereabove. In compartment 14 thereare provided'a plurality of substantially imperforate shelves I00 which are supported from the inner lining member 38 and the partition member II by means of brackets I02. These shelves are preferably arranged in spaced relanship to theme or more walls of the inner lining member 20 and the partition member so that limited circulation of air is permitted between the spaces enclosed by the severalshelves. Large receptacle I04 issuspended within the lower part of compartment I4 by means of bracklms I00." A door III which is preferably of glass is provided at the front of compartment 14 thereby substantially isolating compartment 14 from the compartment I2. Likewise a door H2 and a door II4 'are'provided at the front' of compartments 2 and; 04, respectively. For cooling the compartment I4 the secondary refrigerant evaporating element I is provided. This element consists of a serpentine conduit I22 arranged in intimate heat exchange relation with the outer .walls of the inner lining member which enclose compartment I4 as shown inFig'. 4. This serpentine conduit may be'secured to the lining member as by soldering or the like.

Liquid refrigerant is supplied to the primary refrigerant evaporating element 00 by a condensing unit I30 which is disposed within the machine compartment 24. This condensing unit clined position below the motor compressor unit. Evaporated refrigerant is conducted from the refrigerant evaporating element through a conduit I40 to the motor compressor unit. The compressor compresses the refrigerant and then delivers it to the condenser I34 where it is liquefied.

he liquefied refrigerant is then directed through a small diameter tube I44 to the refrigerant evaporating element 50. This small diameter tube serves to meter the flow of the liquid refrigerant in a manner well understood in the art. Preferably, the suction conduit I40 and the small diameter tube I44 are arranged in heat exchange relation; the air for cooling the. condensing I30 is admitted to the machine compartment 24 through an opening I50 in the bottom of the compartment. This air is circulated over the condensing unit and out through an opening I52 at the rear of the machine compartment. This circulation of air through the machine compartment may be either forcibly or naturally induced. If naturallyinduced, a fine I54 is preferably attached to the rear of the cabinet over the opening I52 to enhance the natural convection effect.

Liquid refrigerant is supplied to the secondary evaporating element I20 from a condenser I80. This condenser is connected to the secondary evaporator by a liquid supply conduit I62 which extends from the condenser to the inlet portion of the serpentine conduit I22 on the bottom of the inner lining member 38. The outlet of the serpentine conduit is connected to the condenser by means of a return conduit I04. The condenser IE0 is arranged in heat exchange relation with a coiled portion (not shown) of the primary refrigerating system as shown and described in Letters Patent No. 2,329,140.

The primary refrigerating system is preferably operated under the control of a thermostat (not shown) so as to maintain a below free? '1 temperature in the refrigerant evaporating element 50. The zones 62 and 64 are thereby maintained at below freezing temperatures for the freezing of substances and the storage of frozen foods respectively. The outer surfaces of the refrigerant evaporating element 50 are also therecomprises a motor and compressor directly connected and arranged within-a sealed casing I32 by maintained at below freezing temperatures and serve to cool the circulating air from compartment 12. In this connection the drip pan 80 may be spaced from the walls of the cabinet any distance desired. The greater the spacing the colder the air in compartment may be. A dry storage zone is thereby provided within compartment I2. The receptacle 06 may be employed for the storage of meats and the like. The shelf serves to insulate a portion of the compartment I2 to provide a warm zone Il0 suitable for the storage of butter or the like.

The secondary refrigerant evaporating element I20 is preferably maintained at or slightly above freezing temperatures so as to provide an above freezing temperature in. the compartment I4. The temperature of the secondary evaporating element is determined by the effectiveness of the heat exchange between the secondary condenser I60 and the low side of the primary refrigerating system as is well understood in the art. Because of the restricted circulation of air between the compartment I4 and the primary evaporating element 00, a high humidity is provided within the compartment since little moisture is removed by freezing upon the evaporating elemeat 50. The latter serves to prevent the formation of excess of moisture within the compartment ill and also to produce a certain amount of circulation throughout the compartment, some movement of air being desirable for the proper preservation of foods.

it will thus be seen that compartments i2 and i are maintained at difierent temperatures and difierent humidities quite independently of each other. Since the natural tendency of cold air is to descend, the partition id which separates the two compartments is not subjected to the eX- tremes of temperatures existing in one or the other of the two compartments whereby a greater en the two zones. At the same time both are in connection i the prigerant evaporating eleint. which es to cool one of the compartments; namely, and prevent the formation of excessive the other compartment it. The "ll aids some in cooling compartment or it the drip pan is spaced from the ow net Wallis to allow a substantial air circula- ""1 throughout compartment '32. In this case the air circulating in compartment i2 is low in temperature and the wall iii is cooled to a low temperature to aid in cooling the air in compartment i i.

Although only a preferred form of the invention has been illustrated, and that -form described in detail, it will be apparent to those skilled in the art that various modifications may be made therein without departing from the spirit of the invention or from the scope of. the appended claims.

I claim:

1. Refrigerating apparatus comprising, in combination, an insulated cabinet having a food storage chamber, refrigerant evaporating means disposed in said chamber for freezing substances and for cooling circulating air, vertically arranged partitioning means arranged to divide said chamber into two compartments that are in direct air circulating relation with said evapcrating means and in communication with each other at one end of said compartments only, means associated with one of said compartments for restricting the circulating of air between said compartment and said evaporating means and a second refrigerant evaporating means arranged in heat exchange relation with said one compartment.

2. Refrigerating apparatus comprising, in combination, an insulated cabinet having a food stortemperature gradient may be established be-.

age chamber, refrigerant evaporating means disposed in the upper part of said chamber for freezing substances and for cooling circulating air, vertically arranged partitioning means arranged to divide said chamber into two compart ments which are in direct air circulating relaticn with said evaporating means and in communication each other at their upper ends only, means associated with one of said compartments for restricting the circulation of air between said compartment and said evaporating means and a second refrigerant evaporating means arranged in heat exchange relation with said one compartment.

3. Refrigerating apparatus comprising, in combination, an insulated cabinet having a food storage chamber, a primary refrigerant evaporating element disposed in the upper part of said chamber for freezing substances and for cooling circulating air, partitioning means arranged to divide said chamber into two compartments arranged side by side on the same horizontal plane and which are in direct air circulating relation with said primary evaporating element and in communication with each other at their upper ends only, means associated with one of said compartments for restricting the circulation of air between said compartment and said primary evaporating element, and a secondary refrigerant evaporating element arranged in heat exchange relation with said one compartment.

4. Refrigerating apparatus comprising, in combination, an insulated cabinet having a food storage chamber, a primary refrigerant evaporating element disposed in the upper part of said chamber and adapted to freeze substances and to cool circulating air, a vertical partition disposed below said primary evaporating element and dividing said chamber into two compartments which are in direct communication with said primary WHITNEY GIFFARD. 

